History: 89 year-old man presented complaining of dizziness and lightheadedness for several months. He has a history of "arrythmia" treated with an implanted cardiac pacemaker.

Findings: CT with contrast demonstrating an intra-axial cystic mass in the posterior fossa, eccentric on the left. Effaces the 4th ventricle with minimal mass effect at the cerebello-pontine angle. Enhancing mural nodule on the anteromedial aspect. Mild dilation of the 3rd and lateral ventricles.

History: 89 year-old man presented complaining of dizziness and lightheadedness for several months. He has a history of "arrythmia" treated with an implanted cardiac pacemaker.

Findings: CT with contrast demonstrating an intra-axial cystic mass in the posterior fossa, eccentric on the left. Effaces the 4th ventricle with minimal mass effect at the cerebello-pontine angle. Enhancing mural nodule on the anteromedial aspect. Mild dilation of the 3rd and lateral ventricles.